Net operating income means rent collected minus vacancy, property tax, insurance and maintenance, not gross rent, and two-family buyers routinely overstate their number by skipping vacancy and maintenance reserves entirely. That single omission can make a mediocre property look like a strong one on paper.
Financing also changes the real return, since a two-family purchase may require a larger down payment than an owner-occupied home under CMHC's lending rules, and that changes your cash-on-cash return even when the cap rate on paper looks identical to another property.
Run your own net operating income before trusting anyone else's cap rate number. Get your hand-reviewed valuation from Joel Dyck.